Microleakage Of Resin Composite Restorations Research Articles

Evaluation of Microleakage and Biocompatibility of Universal Adhesive Containing Titanium Dioxide Nanoparticles: A Comparative In Vitro Study

Background & Objective: Although dental composites have undergone a high level of development in recent years, there are still difficulties including microleakage. The incorporation of nanoparticles (NPs) in dental materials can produce antibacterial effects, but the effect of TiO2 NPs on microleakage has not yet been investigated. The present study aimed to determine the effect of TiO2 NPs incorporation in the universal single bond and pretreatment with them on microleakage of clV cavities using both total-etch and self-etch approaches.
 Materials & Methods: Standard clV cavities were prepared on the buccal surfaces of the sixty non-carious human molar teeth. The restoration of samples was carried out with 6 different methods and randomly divided into six groups of ten subjects. Microleakage in both gingival and occlusal margins was determined after placement in 2% basic fuschin solution for 24h. Biocompatibility of a universal single bond was evaluated by MTT assay.
 Results: In both occlusal and gingival margins in all groups, the application of TiO2 NPs was better than no application. We observed the relatively low cytotoxic effect of TiO2 NPs incorporated in the universal adhesive on NIH-3T3 cell viability.
 Conclusion: Regarding the limitations of the present investigation, using TiO2 NPs with both total-etch and self-etch approaches to universal single bond may lead to a decrease in the microleakage of resin composite restorations.

Influence of Adhesive Systems on Microleakage Pattern of Composite Resin Restorations

AIMS: Microleakage is important for assessing the success of adhesive restorative materials. The aim of this study was to evaluate the microleakage of resin composite restorations bonded with three types of adhesive systems. MATERIALS AND METHODS: Twenty four sound human third molars were used. Class V cavities were prepared on the buccal surface by a diamond cylinder bur No. (1543M). Samples was assigned randomly to three groups (N = 8): Group Ι: Cavities were treated with total etch adhesive system (Adper Single Bond 2Adhesive, 3M ESPE, USA). Group II: Cavities are treated with one step self-etch adhesive system (OptiBond All In One, kerr, USA). Group III: Cavities were treated with two step self-etch adhesive system (CLEARFIL SE BOND, kurary, Japan). Cavities were restored in bulk technique withresin composite (Ceram X, DENTSPLY, USA). Restorations were polished and after storage in water for 24 hours at 37°C the samples were thermocycled between 5-50°C for 300 cycles in water baths then immersed in methylene blue solution for 24 hours. Dye leakage was assessed by examining longitudinal sections in a stereomicroscope at X10magnification. Data were analyzed with Kruskal-Wallis test and Mann-Whitney test at 5%significant level. RESULTS: A significant differences in microleakage were observed among restorations (p < 0.05).One step adhesive bonded restorations demonstrate significantly higher leakage value than two step. No significant differences were observed between total etch adhesive and self-etch adhesive (p>0.05).CONCLUSIONS: The microleakage of resin composite restoration was influenced by adhesive type. One step self-etch bonded restoration was more prone to leakage than total etch and two step bonded restoration

Effect of liner on the marginal integrity of resin composite restorations after selective caries excavation: An In Vitro study

Abstract Aim: The aim of this study is to evaluate the effect of cavity liner on marginal adaptation and microleakage of resin composite restorations placed with and without selective caries excavation. Materials and Methods: Class II cavities were prepared in 64 extracted upper premolar teeth followed by microbiological caries induction to simulate deep carious lesions. Composite restorations were performed: Group 1A: without liner and Group 1B: with resin-modified glass ionomer liner after nonselective caries excavation; Group 2A: without liner and Group 2B: with resin-modified glass ionomer liner after selective caries excavation. Maximum gap thickness was measured using a scanning electron microscope to assess the marginal adaptation, and dye penetration method was used for microleakage assessment. Results: There was a statistically significant difference between the groups in maximum gap thickness based on the type of caries excavation (P &lt; 0.001) but not for the placement of liner. Selective caries excavation groups had higher values at all margins. Microleakage between the groups was significantly different, both at the occlusal (P = 0.006) and gingival margins (P &lt; 0.001), with Groups 2A and 2B showing higher microleakage. Conclusion: Resin composite restorations performed after selective caries excavation showed decreased marginal integrity and liner application did not contribute to any significant improvement in the same.

Effect of resealing on microleakage of resin composite restorations in relationship to margin design and composite type

To determine the relationship between margin preparation design and resin-composite type on microleakage with or without re-application of surface-penetrating sealant. Class-I resin-composite restorations were completed for 128 extracted human molars. Half of the margins were beveled, the other half, butt-joint. Half of each group was restored with Filtek-Supreme (FS), the other half with Esthet-X (EX) using their respective adhesive systems. Margins were etched and sealed with a surface-penetrating sealant, Fortify. The samples were stored in water 24h, and thermocycled (5,000 cycles, 5°C-55°C). Then, samples were abraded using a toothbrush machine (6,000 strokes). Half of the restorations from each sealant group (n=16) were resealed, and the other half had no further treatment. Thermocycling and tooth brushing were repeated. The samples were sealed with nail polish, immersed in methylene-blue for 8h, sectioned, and magnified digital photographs were taken. Three examiners assessed dye penetration. A 2×2×2 multi-layered Chi-Square analysis, using Cochran-Mantel-Haenszel test was conducted for statistical analysis. No difference was observed between sealed and resealed FS and EX restorations with butt-joint margins. In beveled margins, resealing caused significantly less microleakage (P<.01). No differences were found between restorations either sealed or resealed with bevel margins. In butt-joint margins, at the leakage level deeper than 2/3 of the preparation depth, resealed FS showed less microleakage than EX resealed restorations (P<.01). Resealing reduced microleakage in bevel margins, however, in butt-joint margins resealing did not affect the leakage. A significant statistical relationship exists between and within resealing, margin preparation design, type of composite, and microleakage.

Effect of surface pretreatment with two desensitizer techniques on the microleakage of resin composite restorations

This study evaluated the effect of two desensitizing procedures on the marginal microleakage of composite restorations bonded by a two-step etch-and-rinse adhesive. Class V cavities were prepared on the buccal surfaces of 42 extracted premolars at the cementoenamel junction and randomly divided into three groups of 14 each. In group 1 (control), an adhesive (Excite) was applied according to manufacturer's instructions. In group 2, after the application of oxalate desensitizer (BisBlock) to the cavities, the specimens were etched, and Excite was applied and light cured. In group 3, the cavities were treated with CO(2) laser irradiation (1 W power output in a continuous wave mode, 10 s), and then, the specimens were etched and bonded by Excite. All the cavities were restored with a resin composite. After water storage and thermocycling, the specimens were placed in 1 % basic fuchsin blue dye solution. The dye penetration was evaluated using a stereomicroscope. The data were analyzed by using Kruskal-Wallis and Mann-Whitney statistical tests (α = 0.05). There was a significant difference among three groups at the gingival and occlusal margins (P < 0.05). The specimens treated with BisBlock exhibited higher microleakage at both margins than those of the control and laser-treated groups (P < 0.001). There was no significant difference between the control group and group treated with CO(2) laser at both margins (P > 0.05). CO(2) laser did not show a detrimental effect on the marginal sealing ability of the adhesive system used in resin composite restorations. However, oxalate desensitizer adversely influenced the sealing ability of the restorations.

Effect of Three Different Mouthrinses on Microleakage of Composite Resin Restorations with Two Adhesive Systems after Bleaching with 10% Carbamide Peroxide

The aim was to evaluate the effects of Oral-B (OB), Listerine (LN) and Rembrandt Plus (RM) mouthrinses on microleakage of composite resin restorations bonded with two adhesive systems after bleaching with 10% carbamide peroxide. A total of 60 Cl V cavities were prepared on human premolars. The occlusal and gingival margins were placed 1 mm occlusal to and apical to CEJ respectively. The teeth were randomly divided into two groups based on the adhesive system used: Excite (EX) and Clearfil SE Bond (CSE) groups. After composite resin restoration of cavities, thermocycling and bleaching with 10% carbamide peroxide for 2 hours daily for 14 days, the teeth in each adhesive group were further subdivided into three subgroups and were immersed for 12 hours in the three OB, RM and LN mouthrinses. The teeth were then placed in 2% basic fuschin for 24 hours. After dissecting the teeth, microleakage was evaluated under a stereomicroscope at 16×. Data was analyzed with multifactor ANOVA and Bonferroni test at p < 0.05. Microleakage with EX was significantly higher than that with CSE (p = 0.009). Microleakage at gingival margins was significantly higher than that at occlusal margins (p = 0.15). Microleakage with OB was higher than that with LN (p = 0.02). However, there were no significant differences in microleakage between LN and RM (p = 1) and between RM and OB (p = 0.15). In addition, with the EX adhesive system, microleakage with OB was higher than that with LN and RM (p = 0.02). In the present study, microleakage of composite resin restorations was influenced by the type of the adhesive system, mouthrinse type and the location of the cavity margin. Use of some mouthrinses, such as OB after bleaching can increase postrestoration microleakage of resin composite restorations bonded with etch-and-rinse adhesive systems.

The Effect of Oxalate Desensitizers on the Microleakage of Resin Composite Restorations Bonded by Etch and Rinse Adhesive Systems

This in vitro study evaluated the effect of an oxalate desensitizer (OX) on the marginal microleakage of resin composite restorations bonded by two three-step and two two-step etch and rinse adhesives. Class V cavities were prepared on the buccal surfaces of 126 extracted premolars at the cementoenamel junction and randomly divided into nine groups of 14 each. In the control groups (1-4), four adhesives were applied, respectively, including Adper Scotchbond Multi-Purpose (SBMP), Optibond FL (OBFL), One-Step Plus (OS) and Excite (EX). In the experimental groups (5-8), the same adhesives, in combination with OX (BisBlock), were applied. And, in one group, OX was applied without any adhesive, as the negative control group (9). All the groups were restored with a resin composite. After 24 hours of storage in distilled water and thermocycling, the samples were placed in 1% methylene blue dye solution. The dye penetration was evaluated using a stereomicroscope. The data were analyzed using non-parametric tests. The OX application, in combination with OBFL and EX, resulted in significantly increasing microleakage at the gingival margins (p < 0.05), while it had no effect on OS and SBMP (p > 0.05). At the occlusal margins, no significant difference in microleakage was observed after OX application for each of four adhesives (p > 0.05).

Effect of Prerestorative Home‐bleaching on Microleakage of Self‐etch Adhesives

Tooth bleaching has become a routine treatment due to patients' esthetic demands. The aim of this study was to evaluate how prerestorative home-bleaching affected microleakage of resin composite restorations bonded with etch-and-rinse and self-etch adhesives. Fifty extracted human premolar teeth were used. The bleaching agent (10% carbamide peroxide) was applied to the buccal surface of each tooth for 6 hours a day for 2 weeks. The lingual surfaces of the same teeth received no application (control). The teeth were stored in artificial saliva. After 14 days, standardized Class V cavity preparations (2 mm high, 3 mm wide, and 2 mm deep) were made on the buccal and lingual surfaces with all margins in the enamel. They were randomly divided into five groups according to the adhesive systems: an etch-and-rinse adhesive (Single Bond [SB]), two two-step self-etch adhesives (Adper SE Plus [ASE] and One Coat [OC]), and two one-step self-etch adhesives (Adper Easy One [EO] and G-Bond [GB]). All adhesives were applied according to the manufacturers' instructions. The preparations were then restored using the same hybrid composite (Filtek Z250) in one increment and light-cured. The teeth were thermocycled (5/55 degrees C, 1,000x) and immersed in dye, then sectioned, and dye penetration was scored. The data were analyzed using the Kruskal-Wallis and Mann-Whitney U-tests. Although statistically significant differences were found between the adhesive systems in the bleached teeth, no differences were observed in the control groups (non-bleached teeth). There were significant differences between SB/GB, SB/EO, SB/OC, and GB/ASE in the bleached teeth (p < 0.05). When comparing bleached and non-bleached teeth within each adhesive system, only SB and EO produced higher leakage scores when bleaching was applied. The other groups showed no difference in terms of bleaching (p > 0.05). Prerestorative home-bleaching had an adverse effect on microleakage of SB and EO. The effect of prerestorative home-bleaching agents on microleakage of composite resin restorations differs according to the type of adhesive material used.

Effect of halogene light source on marginal microleakage of resin composite restorations

Introduction. Although the technology of production resin composite materials has been improved in the past years, polymerization shrinkage and microleakage still remain the main problem of the resin composite restorations. The most important issues are polymerization control, light source choice, quality and polymerization technique. The aim of this study was to evaluate the effect of the halogen light source on the marginal microleakage of the resin composite restorations class V. Material and Methods. The study included 40 extracted human teeth (20 intact and 20 with caries lesion). Class V cavity was prepared in each tooth. The light curing unit used in this study had irradiance 540 mW/cm2. Cavities were restored with the two resin composite materials, Filtek Supreme (3M ESPE) and Luksogal - Galenika. Microleakage was determined using colored solution of 50% silver-nitrate. Results were obtained using stereomicroscope with 6 times magnification. Color penetration was evaluated on the occlusal and gingival wall. Results. Linear color penetration was observed in all cavities restored using Luksogal. There was significant difference (p&lt;0.01) in color penetration between the occlusal (20.30 ?m) and gingival wall (34.00 ?m). Color penetration was shown in all cavities prepared on intact and caries teeth and restored using Filtek Supreme. Also, color penetration on the occlusal wall (13.80 ?m) was significantly lower (p&lt;0.01) than the penetration on the gingival wall (33.00 ?m). Conclusion. All the tested cavities showed marginal leakage, regardless the tooth or material used. Greater microleakage was noticed when Luksogal was used.

Effect of deproteinization and tubular occlusion on microtensile bond strength and marginal microleakage of resin composite restorations

Dentin adhesion procedure presents limitations, especially regarding to lifetime stability of formed hybrid layer. Alternative procedures have been studied in order to improve adhesion to dentin. Objective: The aim of this study was to evaluate in vitro the influence of deproteinization or dentin tubular occlusion, as well as the combination of both techniques, on microtensile bond strength μTBS) and marginal microleakage of composite resin restorations. Material and Methods: Extracted erupted human third molars were randomly divided into 4 groups. Dentin surfaces were treated with one of the following procedures: (A) 35% phosphoric acid gel (PA) + adhesive system (AS); (B) PA + 10% NaOCl + AS; (C) PA + oxalate + AS and (D) PA + oxalate + 10% NaOCl + AS. Bond strength data were analyzed statistically by two-way ANOVA and Tukey's test. The microleakage scores were analyzed using Kruskal-Wallis and Mann-Whitney non-parametric tests. Significance level was set at 0.05 for all analyses. Results: μTBS data presented statistically lower values for groups D and B, ranking data as A>C>B>D. The use of oxalic acid resulted in microleakage reduction along the tooth/restoration interface, being significant when used alone. On the other hand, the use of 10% NaOCl alone or in combination with oxalic acid, resulted in increased microleakage. Conclusions: Dentin deproteinization with 10% NaOCl or in combination with oxalate significantly compromised both the adhesive bond strength and the microleakage at interface. Tubular occlusion prior to adhesive system application seems to be a useful technique to reduce marginal microleakage.

Effect of Polishing Techniques and Time on Surface Roughness, Hardness and Microleakage of Resin Composite Restorations

This study evaluated the effects of immediate and delayed polishing on the surface roughness, microhardness and microleakage of a microfilled (Filtek A110) and a hybrid (Filtek Z250) resin composite. Standardized preparations were made on the buccal surfaces of 256 bovine teeth; half were restored with each composite (128 teeth per composite). Immediately after curing, gross finishing was carried out with #280 sandpaper. The specimens restored with each composite were divided into two subgroups. The first group (IM) was polished immediately after gross finishing, using three different systems (n=16): Sequence A, Sof-Lex; Sequence B, Flexicups and Sequence C, Flexicups + Jiffy Polishing Brush + Flexibuffs. The specimens were then stored for three weeks in saline 37 degrees C. The second group (DE) was stored for two weeks, then polished with the same systems and stored for one additional week. The controls (n=16) were analyzed without polishing. Five readings per specimen were taken for surface roughness and hardness. After immersion in basic fuchsin, microleakage was evaluated (40x) using standardized scores. The data were analyzed at a significance level of 0.05, with analysis of variance and an SNK test (surface roughness and microhardness) or with Kruskal-Wallis (microleakage). In both composites, only for the sequential technique was there an influence of delay in polishing on roughness (Ra). Flexicups exhibited the highest Ra of the three systems. The IM and Filtek Z-250 groups showed higher hardness than the DE and Filtek A-110 groups, respectively. Dentin margins showed more leakage than enamel margins; the sequential technique produced more leakage than the other techniques in dentin (p<0.05) and delay of polishing was not significant in the majority of situations. In conclusion, several conditions--composite, time and polishing technique--had a significant influence on surface roughness, hardness and microleakage. Generally, immediate polishing produced no detrimental effect compared to delayed polishing.

Effect of the number of thermocycles on microleakage of resin composite restorations.

Thermocycling simulates, in vitro, thermal changes that occur in the oral cavity. The aim of this study was to evaluate the influence of the number of cycles on microleakage. Class V cavities (1.5 mm deep, 3 mm in height and 3 mm in width) were prepared in bovine teeth, restored with a Single Bond/Z250 restorative system (3M/ESPE) and then divided into five groups of ten teeth each: group 1 was not thermocycled (control group), and groups 2, 3, 4 and 5 were thermocycled 500, 1,000, 2,500 and 5,000 times, respectively (5 degrees -55 degrees +/- 2 degrees C, 15 s dwell time). The teeth were immersed in 0.5% basic fuchsin aqueous solution for 24 h, sectioned and the sections with the highest degree of microleakage were selected, scanned and the extent of dye penetration was measured by the ImageTool program. The results submitted to one-way ANOVA showed no significant differences between the groups (p > 0.05). The averages of microleakage values in millimeters were: group 1 (3.92); group 2 (3.13); group 3 (4.48); group 4 (4.33) and group 5 (3.42). Thus, it was concluded that there is no relation between the increase of the number of cycles and the increase in microleakage.